Allergens constitute the most abundant proteins of grass pollen, which is the major cause of allergic disease in temperate climates (Marsh (1975) Allergens and the genetics of allergy; in M. Sela (ed.), The Antigens, Vol. 3, pp 271–359, Academic Press Inc., London, N.Y.)., Hill et al. (1979) Medical Journal of Australia, 1:426–429). The first descriptions of the allergenic proteins in ryegrass showed that they are immunochemically distinct, and are known as groups I, II, III and IV (Johnson and Marsh (1965) Nature, 206:935–942; and Johnson and Marsh (1966) Immunochemistry, 3:91–100). Using the International Union of Immunological Societies' (IUIS) nomenclature, these allergens are designated Lol p I, Lol p II, Lol p III and Lol p IV. In addition, another important Lolium perenne L. allergen that has been identified in the literature is Lol p IX which is also known as Lol p V or Lol p Ib (Singh et al. (1991) Proc. Natl. Acad. Sci, USA, 88:1384–1388).
These five proteins have been identified in pollen ryegrass, Lolium perenne L., and act as antigens in triggering immediate (Type 1) hypersensitivity in susceptible humans.
Lol p V is defined as an allergen because of its ability to bind to specific IgE in sera of ryegrass-sensitive patients, to act as an antigen in IgG responses and to trigger T-cell responses. The allergenic properties have been demonstrated by immunoblotting studies showing 80% of ryegrass pollen sensitive patients possessed specific IgE antibody that bound to Lol p V isoforms (PCT application publication number WO 93/04174, page 65). These results indicate that Lol p V is a major ryegrass allergen.
Substantial allergenic cross-reactivity between grass pollens has been demonstrated using an IgE-binding assay, the radioallergo-sorbent test (RAST), for example, as described by Marsh et al. (1970) J. Allergy, 46, 107–121, and Lowenstein (1978) Prog. Allergy, 25, 1–62. (Karger, Basel).
The immunochemical relationship of Lol p V with other grass pollen antigens have been demonstrated using both polyclonal and monoclonal antibodies (Zhang et al., Int. Arch Allergy Appl Immunol, 96:28–34 (1991); Roberts et al., Int. Arch Allergy Appl Immunol, 98:178–180 (1992); Mattheisen and Lowenstein, Clinical and Experimental Allergy, 21:309–320 (1991); and van Ree et al., J. Allergy Clin. Immunol. 83:144–151 (1989)). Antibodies have been prepared to purified proteins that bind IgE components. These data demonstrate that a major allergen is present in pollen of closely related grasses is immunochemically similar to Lol p V and are generally characterized as Group V allergens.
In view of the prevalence of ryegrass pollen allergens and related grass allergens all over the world, there is a pressing need for the development of compositions and methods that could be used in detecting sensitivities to Lol p V or other immunologically related grass allergens, or in treating sensitivities to such allergens, or in assisting in the manufacture of medicaments to treat such sensitivities. The present invention provides materials and methods having one or more of those utilities.